You have to look at the sky or at a surface of uniform color and not focus on any particular point. Then, we see them, some spots, bubbles or transparent, veiled or blackish threads. What are they? Are they harmful? Why do they appear?

The eye is like an almost spherical hollow ball. Inside it has a wrapper, the retina. The inner cavity of the eye is filled with a viscous liquid called humor or vitreous body. "It is a very thick transparent jelly, which is attached to the retina at several points. It has no blood vessels. In its interior, there are very few cells, and for the most part, it is composed of proteins that form a three-dimensional network or mesh that traps water and that causes the vitreous to behave as a whole, not to flow, "explains the expert.

The vitreous has a key function for the development of the eye. During the embryonic and fetal stage, it serves as a support for the formation of the rest of the eye, but after birth, it no longer has a defined function. Of course, it must remain transparent so that the light reaches the retina located at the bottom of the cavity and let's see well.

We see thanks to the light. It enters the back of the eye and collides with the retina, which is full of photosensitive cells that transform this stimulus into nerve impulses. These reach our brain that interprets them and that is when we are aware of the image before us.

"With aging, vitreous, like the whole human body, tends to deteriorate. It loses water, proteins condense and lose transparency. Then opacities or lumps are formed. When those opacities are put in the middle, the shadow falls on the central retina and we see it darker, "says the doctor. They are the flying flies or black dots, which depending on the form of the vitreous opacity can be a trickle, a spider web, a sheet or a bubble. When moving the view the points are not removed, because they are in our eye.

They usually multiply after the age of 60 and in myopia, they appear earlier. In most cases, it is an unimportant problem. "There is no usual treatment for this problem because the only thing that is effective, surgery, involves greater risks than the vision problem of flies or threads. The operation is reserved for more serious cases where the retina has detached,